Superconducting properties of SiC-buffered-MgB₂ tapes

Production of MgB₂ film on metallic Hastelloy with SiC as the buffer layer was achieved by means of hybrid physical-chemical vapor deposition technique, whereas SiC buffer layers with varied thickness of 170 and 250 nm were fabricated inside a pulsed laser deposition chamber. Superconducting transition temperature and critical current density were verified by transport and magnetic measurement, respectively. With SiC buffer layer, the reduced delaminated area at the interface of MgB₂-Hastelloy and the slightly increased T_c of MgB₂ tapes were clearly noticed. It was found that the upper critical field, the irreversibility field and the critical current density were reduced when MgB₂ tapes were buffered with SiC buffer layer. Clarifying the mechanism of SiC buffer layer in MgB₂ tape in affecting the superconducting properties is considerably important for practical applications.